/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.streaming.api.runners.python.beam.state;

import org.apache.beam.model.fnexecution.v1.BeamFnApi;

/** Interface for doing actual operations on Flink state based on {@link BeamFnApi.StateRequest}. */
public interface BeamStateHandler<S> {

    /**
     * Dispatches {@link BeamFnApi.StateRequest} to different handle functions base on request case.
     */
    BeamFnApi.StateResponse.Builder handle(BeamFnApi.StateRequest request, S state)
            throws Exception;

    /** Handles GET requests. */
    BeamFnApi.StateResponse.Builder handleGet(BeamFnApi.StateRequest request, S state)
            throws Exception;

    /** Handles APPEND requests. */
    BeamFnApi.StateResponse.Builder handleAppend(BeamFnApi.StateRequest request, S state)
            throws Exception;

    /** Handles CLEAR requests. */
    BeamFnApi.StateResponse.Builder handleClear(BeamFnApi.StateRequest request, S state)
            throws Exception;
}
